`unknown-cast-variable` in last function of a file

How are you using the lua-language-server?

Visual Studio Code Extension (sumneko.lua)

Which OS are you using?

Windows

What is the issue affecting?

Type Checking

Expected Behaviour

I have a file with two functions that both cast a local variable to a different type. This works perfectly for the first function but fails for the second (or the last if I add more functions).

Actual Behaviour

Error Unknown type conversion variable item (unknown-cast-variable) for the ---@cast item B inside fu().

Reproduction steps

---@alias A table
---@alias B table

---@type table<number, A>
local items = {}

function fu()
  local item = items[1]
  ---@cast item B
end

function bar()
  local item = items[1]
  -- Error appears here:
  ---@cast item B
end

Additional Notes

No response

Log File

No response

从 issue 中的 Lua 复现开始，跟踪 language server 如何处理跨连续函数的 ---@cast 变量。比较 fu() 中成功的 cast 与 bar() 中失败的 cast；当两个 cast 都能在没有 unknown-cast-variable 的情况下被接受时，即表示完成。